Heat flow, depth–temperature, and assessment of the enhanced geothermal system (EGS) resource base of continental China

This paper focuses on a dataset reflecting the potential for the development of enhanced geothermal systems (EGS) in continental China. Depth–temperature profiles, derived from surface heat flow, thermophysical parameters, the thickness of sedimentary layers, and ground surface temperatures, are the basis of EGS resource assessment. According to up-to-date 1230 pieces of heat flow data, we updated the heat flow measurements and depth–temperature distribution maps in continental China. Subsequently, the EGS resources were estimated using volume method with respect to various depth slices, temperature grades, and provinces, respectively. Results indicate that the total heat content within the depth of 3–10 km is 22.9 × 10⁶ EJ (1 EJ = 10¹⁸ J), of which recoverable part is equivalent to 1.56 × 10⁴ billion tons coal equivalent by the conservative recovery factor (2%). Under the assumption of 30-year-long production life, 10 °C reduction from the original rock temperature, and 2% as the recoverable factor, the production of electric power in continental China is estimated to be 4.56 × 10⁶ MWe. On the basis of the calculation, we delineated four favorable targets for EGS resources exploration, including South and Northeast Tibet, West Yunnan (Tengchong), the southeast coast of China (Zhejiang, Fujian, and Guangdong), and Northeast China (Songliao Basin and Changbai Mountain).